Review of the research on oxides in low-temperature magnetic refrigeration

The discovery of the giant room temperature magnetocaloric effect (MCE) has renewed a remarkable research interest in the field of magnetocaloric materials at low temperatures. Among the various magnetocaloric refrigerants, rare-earth transition-metal oxides are one of the most promising candidates for low-temperature applications. In this study, the magnetic properties of rare-earth transition-metal oxides and their research status are reviewed. Three different systems are introduced in the review: (1) Manganates including RMnO3, RMn2O5 and R2Mn2O7 series; (2) Chromates including RCrO3 and RCrO4 series; (3) Vanadates including RVO3 and RVO4 series. The strong correlation of magnetocaloric effect of materials with crystal structure and magnetic phase transition is summarized. The origin of large MCE and potential applications of these materials are discussed. The purpose of the review is to provide a new idea for the selection, search and design of magnetic materials with enhanced MCE, and to promote the development of low-temperature magnetic refrigeration technology.